Remote Monitoring, by its very nature, involves communication between dissimilar pieces of equipment. For example:

There are a large number of diverse communications protocols use to facilitate this type communication. This page contains an extensive and growing list of protocol standards along with related documentation and links.

Catagory Codes - Each protocol is categorized by the nature of their intended application:

  P Process Automation
  B Building Automation
  A Automotive
  C Chip to chip
  I Industrial Control Systems
  M Automatic Meter Reading
W Power Systems Automation




Name Description A B W P C M I Docs & Links  
1-Wire from Dallas/Maxim   x              
4-20mA Loop Extensively used to connect sensors to monitoring and control systems               Primer
802.2B Wireless communications standard               Comparison  
ANSI C12.18 Automatic meter reading protocols           x    
AS-Interface A low-cost 2-wire sensor/actuator interface. Provides data and power to 62 slave devices over a 100M distance. User Organization:AS-International               Overview  
BACnet Mainly used for building automation and HVAC control. Developed by ASHRAE. User Organization:   x              
Blue Tooth Wireless communications standard. User               Comparison  
BSAP Asynchronous protocol developed by Bristol Babcock (Emerson) suitable for local RS232/RS485 networks and for low-speed phone and radio links.       x       Detailed Summary  
CAN Controller Area Network utilized in many network implementations, including x     x          
CANopen Also known as EN 50325-4. Provides standardized communication objects for real-time data, configuration data and special functions and network management. Used in medical equipment, off-road vehicles, maritime electronics, public transportation building automation and other industries. User Organization: CIA                  
C-Bus     x              
CC-Link For high-speed communication between controllers and intelligent field devices like I/Os, sensors and actuators. User Organization: CLPA       x          
CIP Common Industrial Protocol - A media-independent protocol adapted to EtherNet/IP, DeviceNet, CompoNet, and ControlNet; and other networks.       x       Website  
ControlNet Also known as EN 50170. Uses packet data over 5mbps coax cable. supports multiple controllers. Network lengths up to 1000M (or 25km with repeaters). User organization: ODVA       x          
DALI     x              
DC-BUS [1] Automotive power-line communication multiplexed network                  
DeviceNet Multi-drop communication network between industrial controllers and I/O devices. User Organization: ODVA       x          
DF-1 Asynchronous protocol used to communicate with most Allen Bradley interface modules.       x       Reference Manual  
DirectNet Koyo / Automation Direct proprietary, yet documented PLC interface       x          
DLMS/IEC 62056 Automatic meter reading protocols           x      
DNP3  Used extensively by power utilities to connect substation equipment together.     x         60870-5_v_DNP
DSI     x              
EtherCAT Ethernet based fast Real-Time Master/Slave network using twisted pair wiring. User organization: EtherCAT       x          
Ethernet Global Data (EGD) GE Fanuc PLCs (see also SRTP)       x          
Ethernet Powerlink an open protocol managed by the Ethernet POWERLINK Standardization Group (EPSG)       x          
EtherNet/IP Also known as IEC 61158. An Ethernet implementation of CIP. User organization: ODVA       x          
FINS Omron's protocol for communication over several networks, including Ethernet.       x          
FIPIO A subset of WorldFIP and EN 50170. Optimized for decentralized IO systems. User organization: WorldFIP                
FL-net A Japanese-driven standard based on standard Ethernet technology. User Organization: Open PLC                
FlexRay a general purpose high-speed protocol with safety-critical features x                
FMS x              
FOUNDATION fieldbus         x       Overview
GE SRTP GE Fanuc PLCs       x          
HART  An extension to the 4-20mA Loop spec that enables data communication       x       Specification
Honeywell SDS Smart Distributed System - Originally developed by Honeywell. Currently supported by Holjeron       x          
HostLink Omron's protocol for communication over serial links.       x          
HSE High Speed Ethernet - an extension to Foundation Fieldbus               Specification  
IIC Used to attach low-speed peripheral ICs to a processor or controller.         x     Specification  
IIS (I2S Bus) Serial bus optimized for transfer of audio data               Specification  
IEC 60870-5  Telecontrol of SCADA systems     x         60870-5_v_DNP  
IEC 60870-6     x          
IEC 61107 Automatic meter reading protocols           x      
IEC 61850       x            
IEC 62351 Security for IEC 60870, 61850, DNP3 & ICCP protocols     x            
IEEE-1496 See "S-Bus"                
Interbus Also known as IEC 61158 and part of PROFINET IO. Used to connect sensors and actuators via a serial bus cable, to control systems. Optimized for cyclic I/O data transfer. User ORganization: Interbus Club       x        Basics  
J1587 x              
J1708 RS-485 based SAE specification used in commercial vehicles, agriculture, and heavy equipment. x                
J1939 and ISO11783 an adaptation of CAN for agricultural and commercial vehicles                  
Konnex (KNX) previously AHB/EIB   x              
KWP2000 Keyword Protocol 2000 () - a protocol for automotive diagnostic devices (runs either on a serial line or over CAN) x                
Ladder Logic A rudimentary programming language for PLCs               Overview  
LIN Automobile / Vehicle protocol buses x              
LonTalk Protocol on a chip. User Organization:   x              
M-Bus Automatic meter reading protocols           x      
MECHATROLINK open protocol originally developed by Yaskawa.       x          
MelsecNet supported by Mitsubishi Electric       x          
Modbus     x x x   x   Modbus Website
Modbus Plus A Master/Slave networks using RS-485 token passing for industrial control applications at remote locations. User Organization: Modbus-IDA User Group       x          
Modbus RTU Provides client/server communication between devices connected on different types of buses or networks. User Organization: Modbus-IDA User Group       x          
Modbus-TCP Adds Ethernet communications to standard Modbus. User Organization: Modbus-IDA User Group                
MOST Media Oriented Systems Transport () - a high-speed multimedia interface x                
MTConnect               x    
NMEA 2000 x              
oBIX     x              
OPC Ole for Process Control - A set of software standards developed by Microsoft in collaboration with Process Control HW & SW vendors               Overview  
OPC DA               x    
OPC HDA             x  
OPC UA               x    
Optomux Serial (RS-422/485) network protocol originally developed by Opto 22 in 1982. The protocol was openly documented and over time used for industrial automation applications.       x       Protocol Manual  
PCI A bus standard for attaching peripheral interface boards to the processor of a computer.               PCI Bus Comparison  
PieP An Open Fieldbus Protocol       x          
Powerlink An adaptation of CANopen over Ethernet. User Organization: EPSG                
Profibus Multi Master communication for factory, process and building automation. User Organization: Profibus     x x       Guidelines  
PROFINET IO   Also know as IEC 61158 and IEC 61784. Integrates with PROFIBUS, DeviceNet, and Interbus without changes to existing devices. User Organization: Profibus       x          
RAPIEnet Real-time Automation Protocols for Industrial Ethernet       x          
RCI Remote Command Interface               Specification  
RS-232 A set of electrical and mechanical specifications for a serial communications link between two systems.               Pinouts
Electrical Specs
S-Bus Also known as IEEE-1496. A bus standard for attaching peripheral interface boards to the processor of a computer. Obsolete.               S-Bus comparison  
SERCOS III Ethernet-based version of SERCOS real-time interface standard       x          
SERCOS interface Open Protocol for hard real-time control of motion and I/O       x          
Sinec H1 Siemens       x          
Smart Energy 2.0 Automatic meter reading protocols           x      
SPI Serial Peripheral Interface - Used to attach peripheral ICs to a processor or controller. Very simple.         x     Overview
Protocol Manual
SynqNet An industrial automation network for meeting the performance and safety requirements of machine control applications.       x       Overview  
TTEthernet TTTech       x          
USB A standard that defines the cables, connectors and communications protocols for the connection of peripherals (such as cameras, printers and sensors) to a host system or computer.               Document Set (zipped)  
VAN Vehicle Area Network x                
Wi-Max Wireless communications standard               Comparison  
X10 Controls appliances and other loads through low-speed, uni-directional, power-line carrier communication   x           Protocol  
xAP Open, home automation protocol   x           Website  
X-Modem File transfer protocol               xymodem Reference  
Y-Modem                 xymodem Reference  
ZigBee Automatic meter reading protocols   x           Comparison